Let $F_1 = \left( -3, 1 - \frac{\sqrt{5}}{4} \right)$ and $F_ 2= \left( -3, 1 + \frac{\sqrt{5}}{4} \right).$  Then the set of points $P$ such that
\[|PF_1 - PF_2| = 1\]form a hyperbola.  The equation of this hyperbola can be written as
\[\frac{(y - k)^2}{a^2} - \frac{(x - h)^2}{b^2} = 1,\]where $a, b > 0.$ Find $h + k + a + b.$
Answer: The center of the hyperbola is the midpoint of $\overline{F_1 F_2},$ which is $(-3,1).$  Thus, $h = -3$ and $k = 1.$

Also, $2a = 1,$ so $a = \frac{1}{2}.$  The distance between the foci is $2c = \frac{\sqrt{5}}{2},$ so $c = \frac{\sqrt{5}}{4}.$  Then $b^2 = c^2 - a^2 = \frac{5}{16} - \frac{1}{4} = \frac{1}{16},$ so $b = \frac{1}{4}.$

Hence, $h + k + a + b = (-3) + 1 + \frac{1}{2} + \frac{1}{4} = \boxed{-\frac{5}{4}}.$